Displays play the roles as output devices for showing pictures and texts in the present information society. Along with the development of information products toward compactness, liquid crystal panels have become inevitable equipments in some small portable displays like personal digital assistant (PDA), mobile phones, digital cameras, video games and digital watches.
In a liquid crystal display, an image output is composed of many pixels arranged in array on a liquid crystal panel. Driving of pixels is controlled by a drive module composed of a plurality of transversal signal scan lines (Common) and a plurality of longitudinal data transmission lines (Segment). As shown in FIG. 1, in the prior art, a plurality of signal scan lines 12 and a plurality of data transmission lines 14 are connected to a signal scan drive IC 16 and a data transmission drive IC 18 disposed at two adjacent sides of a panel 10, respectively. The brightness of pixels 11 is controlled by the two drive ICs 16 and 18. In fabrication, a high pressure process and a low pressure process are adopted for the signal scan drive IC 16 and the data transmission drive IC 18, respectively. However, in addition to occupying a larger circuit layout space, this kind of design of arranging the two drive ICs 16 and 18 at two adjacent sides of the panel 10 also reduces space of the panel for image display. Moreover, because all adjacent signal scan lines 12 and all adjacent data transmission lines 14 are densely arranged, a high voltage difference between contacts of two adjacent signal scan lines on the drive ICs 16 and 18 will arise, hence easily having the drawback of signal interference. Besides, when this kind of drive module is used, an external memory (RAM) (not shown) is required for full operation, hence resulting in much inconvenience.
FIG. 2 shows the structure of another drive module in the prior art. A single chip IC 20 is disposed at the lower edge of a panel 10. In addition to connecting a plurality of data transmission lines 14, the single chip IC 20 also connects a plurality of signal scan lines 12. In order to let the layout of the signal scan lines 12 connected to the single chip IC 12 be not too dense to cause difficulty in fabrication, the signal scan lines 12 are divided into a front and a rear section. The signal scan lines 12 of these two sections are connected to contacts at two sides of the single chip IC 20, respectively. In addition to having the inbuilt drive function of the data transmission lines 14 and the signal scan lines 12, the single chip IC 20 also integrates the functions of a memory and a controller. Therefore, the fabrication process of this single chip IC 20 is very complicated. Moreover, in order to match the high pressure process of the signal scan lines 12, the whole single chip IC 20 needs to be processed at a high pressure, hence having a very high cost and thus greatly increasing the fabrication cost of this drive module.
Accordingly, the present invention aims to propose a low-cost drive module of liquid crystal panel to resolve the problems in the prior art.